The Center for Clinical Epidemiology and Biostatistics (CCEB) of the University of Pennsylvania School of Medicine (SOM), in collaboration with the University of the Sciences in Philadelphia (USP), proposes to develop an innovative research training program in clinical pharmacoepidemiology, specifically designed to train clinicians to be rigorous, independent academic investigators able to use the range of approaches available in epidemiology to study the use and effects of medications in populations. The specific aims of the training program are to: 1) provide in-depth knowledge of the research techniques appropriate to clinical pharmacoepidemiology research; 2) provide an understanding of the basic principles of clinical pharmacology; 3) provide opportunities for the study of topics related to clinical pharmacoepidemiology; 4) provide intensive, supervised research experience with mentors in clinical pharmacoepidemiology; and 5) bring together faculty and fellows through participation in seminar series in the CCEB and at USP. Trainees would earn a Master of Science in Clinical Epidemiology (MSCE) degree and be eligible to sit for the Clinical Pharmacology Board exam. The two- to three-year training program consists of: 1) a core curriculum of required courses in clinical epidemiology, research methodology, and biostatistics; 2) required courses in pharmacoepidemiology and pharmacokinetics; 3) required clinical experiences in clinical pharmacology; 4) elective courses in pharmacology, pharmacy practice, or other areas relevant to the trainees' interests and experience; 5) extensive independent readings; 6) mentoring provided by senior methodologists/clinjcal pharmacoepidemiologists, clinical pharmacologists, and biostatisticians; 7) attendance at and participation in research seminars in the CCEB and at USP; and 8) the completion of a mentored independent research project in clinical pharmacoepidemiology. Strengths of the proposed program are: 1) the long history of successful research training programs in the CCEB; 2) the comprehensive course offerings and research programs that are available to trainees; 3) the internationally renowned clinical pharmacoepidemiology program housed in the CCEB; 4) the distinguished pharmaceutical training program offered by USP; and 5) the extensive successful training records of the program director and faculty.